| UNC | Universal Naming Convention |
| UNC | Unique / Universal Naming Convention |
| CNS | Color Naming System |
| NAPTR | Naming Authority Pointer |
| ONS | Object Naming/Numbering System |
| XFN | X / Open Federated Naming Service |
| JNDI | Java Naming and Directory Interface |
| JNDSPI | Java Naming and Directory Service Provider Interface |
| GCB | German Convention Bureau e.V. |
| CRC | Convention on the Rights of the Child Kinderrechtsausschuß |
| IBC | International Broadcasting Convention |
| ITC | international telecommunications convention vgl. Genf, http://www.itu.int |
| ICCC | Inter-Client Communication Convention |
| CBD | Convention on Biological Diversity [engl.] UN-Vereinbarung über biologische Artenvielfalt |
| COTIF | Convention relative aux Transports Internationaux Ferroviaires Übereinkommen über den internationalen Eisenbahnverkehr |
| CCD | Convention on Combating Desertification and Drought [engl.] UN-Konvention zur Bekämpfung der Wüstenbildung |
| CITES | Convention on International Trade in Endangered Species of wild fauna and flora Übereinkommen über den internationalen Handel mit gefährdeten Arten frei lebender Tiere und Pflanzen |
| U | Uniform |
| UWT | Uniform Wall Temperature |
| URN | Uniform Resource Name / Number |
| URA | Uniform Resource Agent |
| URI | Uniform Resource Identifier |
| UHF | Uniform Heat Flux |
| UCD | Uniform Call Distribution |
| NUMA | Non-Uniform Memory Architecture |
| NURBS | Non Uniform Rational B-Spline |
| UCS | Uniform Chromaticity Scale |
| ACU | Army Combat Uniform |
| UCC | Uniform Commercial Code |
| URL | Uniform Resource Locator [Internet] |
| USOC | Uniform Service Order Code |
| URI | Uniform / Universal Resource Identifier |
| BDU | Battle Dress Uniform [engl.] Kampfanzug |
| UNICORE | Uniform Interface to Computing Resources |
| URC | Uniform Resource Characterictics / Citation |
| UCITA | Uniform Computer Information Transaction Act |
| PURL | Persistent Uniform Resource Locator |
| UCMJ | Uniform Code of Military Justice |
| UMA | Unified / Uniform Memory Access / Architecture |
| UDRP | Uniform Domain Name Dispute Resolution Policy |
| ccNUMA | Cache Coherent Non-Uniform Memory Access |
| NCCUSL | National Conference of Commissioners on Uniform State Laws |
| url | Internet Adreßzuweisungs-Datei [uniform Ressource locator] eine Dateiendung |